Can older males deliver the good genes?

Females of many species choose to mate with old rather than young males, possibly because older males pass superior genes on to their offspring. Recent theoretical and empirical investigations have rejuvenated interest in the evolution of mating preferences based on age, and in the relationship between longevity and fitness. If the cost of signalling is a reduction in future survival and reproduction, mate choice based on age is one possible outcome when males signal their genetic quality. These recent investigations highlight the importance of understanding sexual selection from a life-history perspective.     

Phosphoinositides: older than we first thought?

Despite nearly 50 years of study, it is good to see that phosphoinositides are still capable of springing the odd surprise. Signaling by the second messenger phosphatidylinositol 3,4,5-trisphosphate (PtdIns(3,4,5)P(3)) was thought to be absent in yeast, but a recent paper now describes the presence of PtdIns(3,4,5)P(3) in Schizosaccharomyces pombe.     

Does sleep really shorten when we get older?

Sleep and Biological Rhythms -     

Why do older workers have problems with technology?

Why do older workers seem to have problems with technology? In this paper, I will review several possible reasons and illustrate them with evidence, often anecdotal, from our work as ergonomics practitioners. We find that older workers have more to "unlearn" from their accumulated experience. They may suffer from gradual or not so gradual ailing faculties of sight, hearing, dexterity, stamina, memory, and reaction time. They may exhibit a fear of making mistakes, and they may have strongly established preferences and pessimism about technological gimmicks. But the real problem is often that the designers have failed to anticipate the requirements of their users; they have failed to design for a range of abilities broader than their own; they have failed to test their designs with real people; and they have failed to learn from the experience of the market. Getting design right for older users is really only a continuation of getting design right for all.     

Loneliness interventions among older adults: sense or nonsense?

This article focuses on the most important findings of a unique evaluation study of loneliness interventions among older adults. Eighteen interventions have recently been carried out and closely monitored in various parts of the Netherlands. In ten of these interventions the number of participants was sufficiently large to quantitatively determine the effect of the intervention on loneliness. It does not appear to be easy to overcome loneliness: no more than two of the ten interventions resulted in a reduction in loneliness among participants that may be attributed to the intervention. Two other interventions may have had a preventive effect: whereas loneliness increased among members of the control group, it remained more or less constant over time among participants. The effect measurements were followed by process evaluations in an effort to gain insight into the possible reasons why feelings of loneliness were not alleviated among participants in the case of most of the interventions. This resulted in a number of lessons for the future, which may be used as a checklist when designing new interventions projects.     

Can physical activity improve the mental health of older adults?

The world population is aging rapidly. Whilst this dramatic demographic change is a desirable and welcome phenomenon, particularly in view of people's increasing longevity, it's social, financial and health consequences can not be ignored. In addition to an increase of many age related physical illnesses, this demographic change will also lead to an increase of a number of mental health problems in older adults and in particular of dementia and depression. Therefore, any health promotion approach that could facilitate introduction of effective primary, secondary and even tertiary prevention strategies in old age psychiatry would be of significant importance. This paper explores physical activity as one of possible health promotion strategies and evaluates the existing evidence that supports its positive effect on cognitive impairment and depression in later life.     

Peripheral administration of α-MSH reduces fever in older and younger rabbits

In these experiments IV, ICV and intra-gastric administration of α-MSH reduced fever caused by injections of leukocytic pyrogen (LP). 2.5 μg α-MSH injected IV reduced fever caused by IV LP, more so in rabbits over 3 yrs old than in those under 2 yrs of age; 5 mg of acetaminophen given IV had no antipyretic effect in either age group. ICV administration of 25 ng α-MSH reduced fever caused by IV LP injection in the older but not in the younger rabbits. α-MSH given IV (2.5 μg) also lowered fever induced by ICV injection of LP in older but not in younger animals. Both older and younger rabbits showed reductions in fever evoked by IV LP after 2.5 mg α-MSH was given by gastric tube. The results indicate that this peptide which occurs naturally within the brain has potent antipyretic properties when given systemically, presumably as a result of a central antipyretic action. Greater sensitivity to central α-MSH in the older rabbits may account for the reduced febrile response seen in the aged. The findings support previous data which suggest that central α-MSH has a physiological role in the limitation of fever.     

Can stability really predict an impending slip-related fall among older adults?

The primary purpose of this study was to systematically evaluate and compare the predictive power of falls for a battery of stability indices, obtained during normal walking among community-dwelling older adults. One hundred and eighty seven community-dwelling older adults participated in the study. After walking regularly for 20 strides on a walkway, participants were subjected to an unannounced slip during gait under the protection of a safety harness. Full body kinematics and kinetics were monitored during walking using a motion capture system synchronized with force plates. Stability variables, including feasible-stability-region measurement, margin of stability, the maximum Floquet multiplier, the Lyapunov exponents (short- and long-term), and the variability of gait parameters (including the step length, step width, and step time), were calculated for each subject. Sensitivity of predicting slip outcome (fall vs. recovery) was examined for each stability variable using logistic regression. Results showed that the feasible-stability-region measurement predicted fall incidence among these subjects with the highest sensitivity (68.4%). Except for the step width (with an sensitivity of 60.2%), no other stability variables could differentiate fallers from those who did not fall for the sample included in this study. The findings from the present study could provide guidance to identify individuals at increased risk of falling using the feasible-stability-region measurement or variability of the step width.     

Can initial and additional compensatory steps be predicted in young,older, and balance-impaired older females in response to anterior and posterior waist pulls while standing?

The initiation of a single compensatory step in response to balance perturbations has been predicted with accuracies of up to 71%. We sought to determine whether similar methods also could be used to predict the onset of additional compensatory steps in both healthy and balance-impaired older females. Anterior and posterior waist pulls of five different magnitudes were applied to 13 unimpaired young (mean age 23 years), 12 unimpaired older (mean age 71 years), and 15 balance-impaired older (mean age 76 years) women. Body segment kinematic data were recorded at 100 Hz. A step was predicted when the time for the center-of-mass to reach the vertical projection of the boundary of the base-of-support fell below a certain threshold. The results show that 83% of all steps and non-steps were correctly predicted at an optimal time-to-boundary threshold (tau(opt)) of 0.78 s. Step prediction accuracy did not differ significantly by group: 86% of steps and non-steps by young, 84% by unimpaired old, and 82% by balance-impaired old women were correctly predicted at tau(opt) of 0.58, 0.67, and 0.78 s, respectively. Anterior steps and non-steps were predicted more accurately than posterior ones (94% vs. 79% correct at tau(opt) of 0.52 and 0.84 s, respectively) and initial steps were better predicted than additional ones (87% vs. 81% correct at tau(opt) of 0.77 and 0.34 s, respectively). We conclude that this step prediction method reasonably predicts initial and additional steps in the anterior and posterior direction by all three subject cohorts.     

Can increased muscle ROS scavenging keep older animals young and metabolically fit?

Insulin resistance and lipid accumulation occur with aging, perhaps due to mitochondrial dysfunction. In this issue of Cell Metabolism (Lee et al., 2010), older mice overexpressing mitochondrial targeted catalase had reduced muscle mitochondrial oxidative damage, lower intramuscular lipid, and improved insulin sensitivity, suggesting that enhanced ROS scavenging prevents age-associated mitochondrial impairments and insulin resistance.     

Is Europe prepared to meet the oral health needs of older people?

OBJECTIVE: To discuss the preparedness of the social and health care systems and the health workforce in Europe to manage the increasing general and oral health care needs of older adults. BACKGROUND AND DISCUSSION: There are large inequalities across European countries and regions in the demographic, socioeconomic and health status of the elderly. The ageing of the population and the economic crisis put at risk the existing social and health care systems and are expected to further widen the existing inequalities. Despite the increase in funding for the general health care, public funding for dental care has reduced, limiting the access for the disadvantaged elderly. Dental care is isolated from health care policies and funding. At the same time there is a significant shortage of adequately trained personnel in the care of the elderly and a shortage of training opportunities particularly at a postgraduate and continuing education level. CONCLUSION: Immediate action is needed and appropriate strategies need to be implemented. Oral health prevention, delivery policies and funding should be integrated within the general health care system. Clinical protocols and guidelines need to be developed on the oral care of the elderly. Interdisciplinary training in the care of the elderly needs to be implemented for all health care workers (dentists, physicians, nurses, health care aids, social workers) at all education levels to enhance comprehensive care.     

Weight-modification trials in older adults: what should the outcome measure be?

Background

Overweight older adults are often counseled to lose weight, even though there is little evidence of excess mortality in that age group. Overweight and underweight may be more associated with health status than with mortality, but few clinical trials of any kind have been based on maximizing years of healthy life (YHL), as opposed to years of life (YOL).

Objective

This paper examines the relationship of body mass index (BMI) to both YHL and YOL. Results were used to determine whether clinical trials of weight-modification based on improving YHL would be more powerful than studies based on survival.

Design

We used data from a cohort of 4,878 non-smoking men and women aged 65–100 at baseline (mean age 73) and followed 7 years. We estimated mean YHL and YOL in four categories of BMI: underweight, normal, overweight, and obese.

Results

Subjects averaged 6.3 YOL and 4.6 YHL of a possible 7 years. Both measures were higher for women and whites. For men, none of the BMI groups was significantly different from the normal group on either YOL or YHL. For women, the obese had significantly lower YHL (but not YOL) than the normals, and the underweight had significantly lower YOL and YHL. The overweight group was not significantly different from the normal group on either measure.

Conclusions

Clinical trials of weight loss interventions for obese older women would require fewer participants if YHL rather than YOL was the outcome measure. Interventions for obese men or for the merely overweight are not likely to achieve differences in either YOL or YHL. Evaluations of interventions for the underweight (which would presumably address the causes of their low weight) may be conducted efficiently using either outcome measure.